CAJ | 학술논문

样本前处理是影响离子选择电极测土时效性的关键环节。以缩短静置时间为目的，该文探讨了高分子絮凝剂Superfloc127用于土壤硝态氮浸提前处理操作的可行性。首先，基于相界电位模型对Superfloc127加入土样硝态氮浸提液后电极反应动力学过程进行建模分析，理论可行性验证后，开展测土试验，分析其对自制全固态电极（PPy-NSISE）及商用电极（PVC-NISE）电化学性能的影响。结果表明：使用Superfloc127后，样本制备时间由1.5 h缩短至10 s；PPy-NSISE及PVC-NISE响应斜率分别为-51.4和-52.1 mV/Decade，检测灵敏度无明显改变，测土结果与标准结果之间的决定系数分别为0.69和0.31；连续测定12 h后，PPy-NSISE和PVC-NISE的响应斜率分别降低至-35.1和-25.4 mV/Decade，性能不可恢复。通过理论解析及大量分析试验证明，絮凝剂Superfloc127无法应用在基于离子选择电极法的土壤硝态氮快速分析，提高土壤前处理效率的研究工作仍需深入开展。
양본전처리시영향리자선택전겁측토시효성적관건배절。이축단정치시간위목적，해문탐토료고분자서응제Superfloc127용우토양초태담침제전처리조작적가행성。수선，기우상계전위모형대Superfloc127가입토양초태담침제액후전겁반응동역학과정진행건모분석，이론가행성험증후，개전측토시험，분석기대자제전고태전겁（PPy-NSISE）급상용전겁（PVC-NISE）전화학성능적영향。결과표명：사용Superfloc127후，양본제비시간유1.5 h축단지10 s；PPy-NSISE급PVC-NISE향응사솔분별위-51.4화-52.1 mV/Decade，검측령민도무명현개변，측토결과여표준결과지간적결정계수분별위0.69화0.31；련속측정12 h후，PPy-NSISE화PVC-NISE적향응사솔분별강저지-35.1화-25.4 mV/Decade，성능불가회복。통과이론해석급대량분석시험증명，서응제Superfloc127무법응용재기우리자선택전겁법적토양초태담쾌속분석，제고토양전처리효솔적연구공작잉수심입개전。
phase boundary potential model was built to prove the ignorable influences produced by Superfloc127 on the solvent polymeric ISE with the inner filling solution. The calculated results of the phase boundary potential model showed that less degradation of the linear detection ranges (LDR) was observed when Superfloc127 was added into the nitrate sample. Theoretically, Superfloc127 was demonstrated acceptable influences on the performance of nitrate ISE. And then, soil samples was prepared to further verify the applicability of Superfloc127. Soil testing was carried out by the self-developed PPy (NO3--N)-membrane nitrate solid-state ISE (PPy-NSISE) and the commercial PVC-membrane nitrate ISE (PVC-NISE). The previous developed soil macronutrient automatic detecting stand was integrated for the measurements throughout the whole study. The effects of Superfloc127 on the performances of PPy-NSISE and PVC-NISE were evaluated by comparing the response sensitivities in standard nitrate solutions. The concentrations of superfloc127 were artificially controlled to 0, 25, 50 and 75 mg/L. 10 soils covering 4 different types were selected. Each soil was divided into three sets. Soil set1 was measured with ultraviolet spectrophotometry. Soil set2 was pretreated without Superfloc127 and analyzed by the ISEs. Soil set3 was pretreated with Superfloc127 and analyzed with the ISEs. Results showed that the standing time, which represented the duration from the ending instant of the shaking process to the instant of obtaining transparent soil extracts, was enormously shortened from 1.5h to 10s by the addition of Superfloc127. The PPy-NSISE and the PVC-NISE produced good sensitivities with the response slopes of -51.4 and -52.1 mV/decade. Neglectable influence made by Superfloc127 was observed on the changes of sensitivities of PPy-NSISE and PVC-NISE. The determination coefficient (R2) of linear regression between ISEs based soil NO3--N measurements and the UV-VIS results were 0.69 and 0.31 for PPy-NSISE and PVC-NISE, respectively. After continuous determination of 12h, the absolute response slopes of the PPy-NSISE and the PVC-NISE were reduced to 35.1 and 25.4 mV/decade. Moreover, the ISE performance couldn’t be recovered even by the re-activation process. In summary, Superfloc127 could greatly improve the efficiency of soil pretreatment. But it will fasten the ISE deteriorating promptly. Therefore, it was not recommended to use Superfloc127 in ISE based soil NO3--N detection. Researches should be carried out to clarify the mechanism of Superfloc127. The attempts of enhance the pretreatment efficiency of ISE based soil detection were greatly encouraged.